1. Field of the Invention
The present invention relates to a method of evaluating contact characteristics of an object having a roughness.
2. Description of the Related Art
When friction characteristics between objects are discussed, it is essential to understand a contact state between the surfaces of the objects. In this case, it is important to understand a real contact state between the objects but not an apparent contact state. This case is also applied to a case where a contact state of a tire rolling along a road surface having irregularities. In other words, the friction characteristics and dynamic characteristics of the tire are evaluated, and when it is to be predicted, it is necessary to obtain details of the real contact state between the tire and the road surface as much as possible.
Japanese Patent Application Laid-Open (JP-A) No. 2003-240681 discloses a technology of setting a tire on a replica model of a road surface with a plurality of grooves formed thereon, measuring a depth of the tire that penetrates into a groove between projections of the replica model, and evaluating how the road surface and the tire contact each other. JP-A No. 2003-240681 also discloses a technology of evaluating how the road surface and the tire contact each other by bringing the tire into contact with the replica model that is manufactured with a transparent plate based on an actual road surface model, and observing a contact surface between the two from the opposite side of the contact surface.
However, in the technologies disclosed in JP-A No. 2003-240681, it is difficult to obtain the details of the real contact state of the contact surface between the road surface and the tire. Further, it is not easy to create and change the replica model of the road surface, and besides, it takes time and effort to evaluate the replica model.